Buoyancy compensators are known which include ballasts or cartridge weights for compensating buoyancy. For example, Patent Literature 1 discloses a buoyancy compensator that includes a vest configured to be worn by a scuba diver and pockets that are positioned on both front panels and into which ballasts are removably inserted. In this buoyancy compensator, the ballasts are linked to the pockets by means of buckles. Further, Patent Literature 2 discloses a buoyancy compensator in which ballasts are removably inserted pockets that are positioned on both front panels and enabled to be openably closed via zip fasteners.